1. Field of the Art
The present invention relates to a thermo-magnetic recording device in which a magnetized latent image is formed on a magnetic layer, and also to the art of initializing the magnetic layer through magnetization in the same direction over its entire recording area.
2. Related Art Statement
There is known a thermo-magnetic recording device in which a magnetized latent image is produced on a magnetic layer made of a ferromagnetic substance, by means of locally heating the magnetic layer. Such a magnetized latent image produced on the magnetic layer is utilized for obtaining a so-called "magnetic picture" or "magnetography". Usually, the magnetized latent image is produced on the magnetic layer by means of reversing the N-S direction (direction of magnetization) of individual locations (segments) of the magnetic layer which has been initialized through unidirectioal magnetization, i.e., magnetization in the same N-S direction over an entire recording area of the layer. The initialization of the magnetic layer is carried out by positioning the magnetic layer in a magnetic field produced by a magnetic-field generating device, in the conventional thermo-magnetic recording device.
3. Problem Solved by the Invention
However, the above-identified thermo-magnetic recording device of a conventional type requires a comparatively high, external magnetic field for initializing the magnetic layer, since the magnetic layer is initialized solely by the external magnetic field. In order to meet that requirement, the conventional recording device must employ a large-sized magnetic-field generating device. In association with the above-indicated problem, the conventional thermo-magnetic recording device has another disadvantage of an unsatisfactory efficiency of magnetization of the magnetic layer.